It is often desirable to position a tool within a wellbore in order to perform a wellbore operation, such as perforating a casing, or sliding a sleeve for opening and closing a port in order to effect hydraulic fracturing and, subsequently, to receive hydrocarbons from a reservoir.
Contemporary wells often extend over significant distances and may be characterized by signficant deviation. In order for a locator to be positioned at or near the extremities of such wells, the locator is configured so as not to offer significant resistance while it is being deployed downhole. However, with a conventional locator, in minimizing its frictional resistance, the reliability of a locator in locating a wellbore, and enabling proper positioning of a tool for a downhole operation, suffers. This is because successful locating is often indicated by sensed resistance to overpull applied to the workstring, and there is greater risk that overpull, in circumstances where the locator is configured to offer minimal resistance while travelling though the well, may be confused with other forces that are merely dislodging the workstring from another form of interference within the wellbore. This is especially true for extended reach wells.